The dyeing of the Chicago River has been an annual tradition for more than 50 years. Each year, on the Saturday before St. Patrick’s Day, the river is dyed emerald green.

More than 40 pounds of a vegetable-based dye is used to transform the river. The process begins at 9am and takes approximately an hour to complete. The results are beautiful but temporary – lasting only about five hours.

Video Produced by Matthew Stanton